point of the needle; and if the magnetism at this end
is the same with that in the other, the point of the needle will of
course be attracted by this end too."
"Certainly," said Rollo's mother.
Then he brought down the other end of the bar towards the needle. This
other end was a little bigger than the one which he had tried first,
because the file had been a little bigger at that end. But the needle,
instead of being drawn towards it, as it had been towards the other end,
began to move slowly away from it.
"Why, it is going away," said Rollo.
His father did not answer, but immediately raised the bar and put it
down upon the other side of the point, and then the point began to move
away back again; being evidently driven away from the large end of the
magnet, on whichever side it was presented.
Then Rollo's father reversed the magnet again; that is, he brought the
smaller end towards the needle as at first. The point of the needle was
now attracted, that is, drawn towards the magnet; and then when he
changed it again, and brought the large end to the needle, it was always
_repelled_; that is, driven away again.
"Now you see," he said, "that the small end of the magnet attracts the
point of the needle, and the large end drives it away. That shows that
the magnetism in the two ends is of two different kinds.
"And now," he continued, "there is one thing more which is remarkable
about it; and I want you to observe it very carefully. You see," he
says, "that the small end of the magnet attracts the point of the
needle. But if I try it now upon the other end of the needle, where the
eye is, it will _repel_ that, just as the large end of the magnet repels
the point."
He tried it, and the result was just as he had said. And he repeated the
experiment in a great many ways, and they always found that the large
end of the magnet would draw the eye of the needle towards it, and drive
the point away; and the small end of the magnet would draw the point of
the needle, and drive the eye away. This proved, as Rollo's father said,
some great difference between the magnetisms of the two ends. "And you
see," he added, "that it is a difference in _kind_, not merely a
difference in _degree_."
"But one thing seems strange to me," said Rollo's mother, "and that is,
that both ends of the magnet don't attract the point of the needle, just
as both of them attracted the nail."
"And the sand," said Rollo.
"Yes," added his
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